It came after an argument between the two over a cup of hot water, which Au later allegedly splashed on Raksona.

Raksona told the court she had worked long hours that day, when Au asked for a cup of hot water. When Au received the water, however, she said it was not hot enough, the helper said.

"She started staring at me and kept staring," said Raksona, speaking through two interpreters who translated her statements from Bengali to English then to Cantonese.

The helper did not understand Cantonese and knew only limited English, the court heard.

Au then asked Raksona at least twice to test the temperature of the water by taking a sip from the cup, but the helper said: "I told her I would not drink because she had already drunk from the cup."

Au then allegedly pulled down Raksona's T-shirt and poured the hot water on her chest, the helper said.

Au appeared in court yesterday in a wheelchair. She wore a neck brace and had bandages wrapped around her wrists.

Medical reports cited by prosecutor Matthew Chong Chun-sang showed that when Raksona was admitted to hospital, the reddened area on her chest accounted for about 2 per cent of her body. She was diagnosed with first-to-second-degree burns on her chest.

The court also saw CCTV footage of Raksona in the lift, appearing to be in pain, as she left the scene after the incident.

Judge Pang Chung-ping heard that Raksona had worked at three places although her contract specified only one place of work.

During cross-examination, defence counsel Judy Ma put to the helper that she did not know her contract details well. When probed, Raksona had difficulty recalling her employer's name and the size of the flat which she was supposed to work in.

She also said Au, whom she referred to as "madam", was not her employer according to the contract. She was employed by a person named Leung, whom she called " ", or "boss".

The case continues today.